Printing press



April 1942- w. w. DAVIDSON 2,280,799

PRINTING PRESS Filed Oct. 3, 1939 4 Sheets-Sheet l 1942- w. w. DAVIDSON 2,280,799

PRINTING PRESS Filed Oct. 3. 1939 4 Sheets-Sheet 2 April 1942- w. w. DAVIDSON 2,280,799

PRINTING PRESS Filed 0st. 3. 1939 4 Sheets-Sheet a April 28, 1942. w. w. DAVIDSON PRINTING PRESS Filed 001.- 3. 1939 4 Sheets-Sheet 4 Patented Apr. 28, 1942 v PRINTING PRESS William Ward Davidson, Evanston, 111.

Application October 3, 1939, Serial No. 297,745

16 Claims.

In some types of printing presses it is necessary to provide a sheet delivery apparatus which grasps the sheet and draws it away from the printing rolls. With small sheets an efllcierit stripping blade may be satisfactory, but with large sheets, especially thin sheets which have very little rigidity, a press with such a stripper cannot throw the sheets out uniformly and dependably. With large presses it is therefore customary to provide'means for gripping the leading edge of the sheet adjacent to the printing rolls and pulling the sheet away to a desired position at which it is released to fall onto a stack. These gripping means are sometimes carried by chains and are appropriately called chain deliveries.

It has also been common to provide gripping means on the printing cylinders as on the blanket rolls of an offset printing press. This latter type of gripping means, together with a registration stop associated therewith, has been considered necessary to secure accurate registration. These registration grippers usually passed the sheet to the delivery grippers, which were carried by their chains around sprockets tangential to the blanket roll.

centric with the blanket roll with resultant simplicity and compactness. According to one form of the invention a single gripping mechanism is made to serve both purposes with resulting economy and simplicity.

The compactness and simplicity are especially notable and satisfactory because of the use of a particular type of press in combinationv with the i above described feature of having the chain delivery run around one of the printing cylinders. The press referred to is an oifset press in which the blanket roll is positioned generally below the platen roll, as in a two-roll press in which the upper roll serves both as a plate roll and a platen roll. With this type of press the sheet is printed on its underside, and it has been common therefore to carry it half-way around the blanket roll so as to turn it over. Thus, the sheet is fed into the press at one side thereof, carried half-way around the blanket roll, and ejected from the press'at the same side of the press on which it was fed to the press. This fact is ingeniously used according to the present invention by providing a chain gripping mechanism in which the grippers follow the simple path of a single closed loop. In short, the chains form a single loop extending around the blanket roll, approaching it and departing According to the present in-' vention the chains are carried on sprockets con- REISSUED DEC 4 1945 Gil from it on the same side 0! the press, namely the side at which the sheets are fed and delivered. As the chain delivery grippers approach the blanket roll and pass over it, the sheet is fed against registration stops on the blanket roll, and the grippers (either on the chain or on the roll or both) grip the sheet to hold it against the stops and thus insure accurate registration. As the sheet passes half-way around the roll it is gripped or continues to be gripped by the grippers carried by the chain which draw it away from the roll to a delivery position at which time the grippers are opened and the sheet is dropped on a stack. I

Additional advantages and objects of the invention will be apparent from the following description and from the drawings, in which:

Fig. 1 is a somewhat diagrammatic view of one form of invention chosen for illustration.

Fig. 2 is a somewhat diagrammatic sectional illustration showing the grippers of the roll gripping a sheet which has just been fed to them. while the grippers of the chain remain open.

Fig. 3 is a corresponding view showing the chain grippers stripping the sheet from the blanket roll.

Figs. 4 and 5 are somewhat diagrammatic illustrations indicating the final steps in the operation of the feeding mechanism.

Fig. 6 is a somewhat diagrammatic fragmentary plan view of the registration and delivery mechanism of Figs. 1 to 3.

Fig. 7 is a somewhat diagrammatic fragmentary detail sectional view taken approximately on the line 1-1 of Fig. 6.

Figs. 8 and 9 are views corresponding to Figs. 6 and '7 but showing a modified and simpler form of the invention.

Two preferred embodiments of the invention have been shown in the drawings and will hereinafter be described all as required by section 4888 of the Revised Statutes but many other forms could be used within the spirit of the invention. v

In the form of the invention chosenfor illustration, the printing press includes a frame l0, printing rolls H and I2, inking rolls l3, dampening rolls l4, final feeding mechanism indicated generally at If, and preliminary feeding or separating mechanism indicated generally at I 1, all of which may be of conventional types. The separator I I separates sheets from a stack l8. Of course, the term printing press might be used more narrowly to include only the printing ro ls II a d The printing roll II is a dual purpose roll, having a plate 2I on one side thereof and a platen surface 22 on the other side thereof. The roll I2 is a blanket roll or transfer cylinder, being provided with a blanket 23. It is thus seen that in its illustrated form the press is of the type known as a two-roll offset press. In the general operation of this press the plate 2|, which bears the matter to be printed, is rotated in contact with the dampening rolls I4 and is then inked by the inking rolls I3. It then rotates in direct contact with the blanket 23, transferring the ink thereto. During this application of ink to the blanket 23, the blanket roll I2 makes a revolution without any sheet in contact therewith and hence without performing a printing function. On its next revolution a sheet is fed to the blanket roll I2 and pressed thereon by the platen surface 22 of the roll II so that the ink on the blanket 23 is printed onto the sheet. The term impression roll" will be confined herein to the member such as the roll l2 which actually applies the ink to the sheets as distinguished from platen rolls which may have been called impression rolls in other patents.

The sheet separating and feeding means may be of any suitable form. It is illustrated as including an advancing roller 26 which is driven intermittently to draw a sheet from the pile I8 at the proper time during each revolution of the roll I I, a retard roller 21 for preventing more than one sheet from being fed at a time, and pull-out rollers 28 for drawing the sheets out after the driving of roller 26 has ceased, the roller 26 being provided with an overrunning clutch. Inclined conveyor belts 29 urge the sheet against the side guide 3| to provide lateral registry against stop fingers 32 to provide preliminary end registry. While the sheet is thus pressed against stop fingers 32, pressure roller 33 is lowered by the cam 34 of Fig. 5 to cooperate with feed rollers 36 in gripping the sheet. When the sheet is thus firmly gripped, cam 31 of Fig. 4 drives a gear segment 38 to rotate stop fingers 32 and feed roller 36 to feed the sheet, the shape of the cam 31 and the positions of the parts being such that the sheet is rapidly moved at a speed in excess of the peripheral speed of rolls II and I2.

To provide final accurate registration, stop fingers M are provided on roll I2 as seen in Fig. 2, and the sheet '42 is fed against these stop fingers by feeding roller 36 actuated, as stated, by cam 31. The sheet 42 is preferably overfed slightly by roller 36 so as to be buckled and pressed firmly against the stop fingers 4I. While I it is thus pressed firmly against the stop fingers 4I, gripping fingers 43 are closed upon the sheet 42, clamping it against an anvil 44. These grippers comprising the fingers 43 and anvil 44 hold the sheet firmly in its registered position and carry it beyond the line of the bite between rolls I I and I2 where it is firmly seized by these rollers. Once it is seized in this bite the accuracy of registration is determined since the rolls II and I2 sprocket 5| mounted on a shaft 53 carried by the frame I8 of the press. Carried by the chains 48 and extending between them are three angle bars 52 spaced apart on the chains 9. distance corresponding to the periphery of the sprocket 49. Each angle bar 52 carries anvil fingers 46 and supports the grip fingers 41 which are carried by and keyed to shaft 53. The shafts 53 are journaled in brackets 54 carried by angle bars 52, Eachshaft 53 has an operating lever 56 secured at its end, the lever 56 bearing a roller 51 which is adapted to engage cam 58.

As each bar 52 approaches the roll I2 or the feeding position thereon, roller 51 rides up on cam 58 thereby turning shaft 53 and opening grip fingers 41 to the position shown in Fig. 2. The grip fingers 43 are in the meantime held open by cam 59 engaging roller 6I on arm 62 which actuates shaft 63 carrying the grip fingers 43. When the sheet 42 has been fed against the stops 4|, roller 6I rides off of the high portion of cam 59 and permits fingers 43 to close on the sheet 42.

After the rolls rotate further and the sheet 42 has been gripped in the bite between rolls II and I2, roller 51 rides oil of cam 58, permitting the second set of grip fingers 41 to close upon the sheet 42, as seen in dotted lines in Fig. 3, under the influence of spring 64. After fingers 41 have closed upon the sheet 42, roller 6I rides onto the highest portion 65 of cam 59 thereby opening the first grip fingers 43 to the position shown in Fig. 3. The bar 52 is now carried by the chains 48 away from the roll I2, the grippers 46 and 41 carried by the bar 52 pulling the sheet 42 off of the roll I2 as seen in full lines in Fig. 3. It will be observed that because of the fact that the two sets of grippers are in alignment through a substantial part of the revolution of roll I2 the closing of one set of grippers and the opening of the other may be performed quite leisurely and there is no necessity for delicate adjustment of these opening and closing times as would be the case if a sheet was being passed from grippers on one roll to grippers on another roll or a chain tangentially disposed with respect to the first roll.

The sheet 42 continues to be gripped by the grippers 46 and 41 until the sheet has been drawn to a position over the pile 66 or over any other suitable discharge receptacle or table, at which time the roller 51 strikes cam 61, and the grip fingers 41 are opened to release the sheet 42 so that it may drop upon the pile 66.

As the roll I2- continues to rotate, roller 6I rides off of the extremely high portion 65 of the the cam 59 and onto the intermediate portion 68 thereof, thereby permitting the fingers 43 to assume an intermediate position approximately even with the outer ends of stop fingers 4I so that they in effect form an overhanging extension for the stop fingers M to positively prevent the next sheet 42 from buckling over and slipping past the stop finger M. It will also be observed that as the sheet 42 is fed to the stop fingers H 7 the gripper fingers 41 are positioned approximately even with the top of the stop fingers M and have upwardly curved toes so that they also aid in guiding the sheet 42 to its proper position against the stop finger 4|. .As a matter of fact, at the time that the sheet is fed to the stop finger 4I it is inclined somewhat toward the feed roller 36 so that when the sheet strikes the stop 4I it tends to slide down the stop 4I (if not already at the base thereof) and come to rest at aaaoneo the proper point in the corner formed by the stop 4| and the anvil 44.

The grip finger 41 is not closed on the sheet 42 until after the sheet 42 has been engaged by the 'rolls II and I! for the reason that this may give greater certainty of registration in that there will be absolutely no chance that movement of the grip fingers 48 and 41 with respect to the roll I! will shift the sheet 42. In short, during the crucial period this form of the invention contemplates that the sheet 42 will be in control of the gripping fingers 43 and the anvil 44 which are immovable with respect to the roll I! except the opening motion of gripping fingers 48, which motion does not occur during the crucial registration period.

It will be observed that the anvil 44 is in fact a bar extending across the roll I2 and it may be the bar used for securing one end of the blanket 28. This anvil or bar 44 is notched as seen at H to receive the anvil fingers 48. Although experience may show that with some presses more grippers are desirable for the chain delivery, it is believed that two grippers each comprising an anvil 48 and a gripping finger 41 will be sufiicient if they are positioned just close enough together to receive the narrowest sheets which are likely to be run on the press, being spaced approximately equally from the center of the roll. It may be desirable to provide a larger number of the registration grip fingers 43 and to make them adjustable so that one of them may always be'positioned near each outer edge of the sheet with intermediate grippers in the case of wide sheets so that the sheet may beheld with maximum firmness. To this end the gripping finger 48 may be adjustably positioned on shaft 63 by set screw 13, the stop finger 43 being maintained in constant angular position with respect to shaft 88 by some sort of splining arrangement or non-circular engagement with the shaft 88. A separate collar 14 may be provided for effectively connecting a spring 18 to shaft 83 to urge the fingers 48 in'the closed direction.

As seen in Fig. '7, the hub" of the roll I2.

rotates with the roll and, indeed, may be used for driving the roll. It is therefore necessary that the earns 88 and 59 be supported independently of the shaft I8, which carries roll l2, and therefore-brackets 8| may be provided for these cams as seen in Fig. 6, these brackets of course extending around a moving part of the press to a stationary portion of the frame.

, It will be observed that the end walls of roll I! are cut out as seen at 83 and the end walls of roll II are cut out as seen at 84 for the purpose of making room for the passage of the transverse members of the chain delivery, namely the bar 52 and the shaft 53. If, as illustrated in Fig. 1, the chain 48 is of a length corresponding to three revolutions of blanket roll l2, it must be provided with a crossbar 52 for each revolution. In this event the walls of roll H should be cut out at 85 at a position diametrically opposite the cut-outs 84. However, if chain 48 were one revolution longer, the crossbars 52 could be spaced two revolutions apart and the cut-out 85 would not be needed. -It will be observed that it is not necessary for these transverse members or any other part of the chain delivery to contact either the roll II or the roll I! since the sheet is registered independently of their exact positioning with respect to the rolls l I and 12. This is very desirable because if it is attempted to position the chain delivery with exactitude with roll II. In view of the common knowledge for the necessity of extreme accuracy of registration for fine printing work, it may be surprising that this registration can be accomplishedthrough the aid of grip fingers carried by the chains 48. It is accomplished, however, by the very simple expedient of utilizing stop fingers 4| carried by the roll I! and taking advantage of the fact that regardless of variations in the relative positioning of cross bars 52' with respect to the roll I! on successive occasions of their meeting, there will ordinarily be no variation in their relative positions during the occasion of one meeting after the links by which the cross bars 82' are carried have been fully seated on the sprocket wheels. It has previously been contemplated to accurately position a crossbar such as the crossbar 52', carrying gripping fingers and even stop means, by a V-type of coaction between such cross-bar and the roll l2 which would automatically self-position the crossbar. Although this is a possible way of obtaining at least fairly good registration, the method illustrated in Figs. 8 and 9 is considerably simpler and at the same time more accurate and also quieter in operation.

The gripping fingers 41' are carried and operated by shaft 53' as seen in Figs. 1 to 7, al-

though they may be longitudinally adjustable thereon if desired and more than two of them may be provided. These gripping fingers 41' are controlled by roller 51' in coaction with stationary cam 88. The position of cam 88 and the angularity of chain 48 should be such that at the time the roller 51' rides off of the cam 88 the links 81 to which the crossbars 52 are secured have become firmly seated on sprocket 88. It is not essential that the links 81 assume exactly the same position on the sprocket 88 each time that they engage it, but it is merely essential that once they are seated thereon they should not move with respect to it until after the sheet has been seized in the bite between the rolls H and i2. To this end the chain 48' could extend at a steeper angle than shown in Fig. 9 or the cam 88 could be extended to the left if it should be found that the fingers 41' were closing before the crossbar 52' had found its final position. Some suitable means, not shown, should be provided for shifting the shaft 53 in a direction to tighten the chains 48.

Fingers 41' will be urged to the closed position by springs 89. It is possible that if these springs are exceptionally strong the cam 86 may result in rocking the bar 52' slightly and thereby causing an undesirable movement of the sheet 42 with respect to the stop fingers 4|. If such should develop, this can be remedied by replacing the springs 88 with weaker springs. If with a particular press and a particular type of work it is found that the sheet is not then gripped firmly enough, other means for operating the grip fingers 41' may be provided. For example, they could be operated by beveled pins operating arms at each end of the shaft 53, each of the beveled pins being moved in a direction-parallel to the shaft by cams engaging the ends thereof so that insure that the link 81 was firmly seated on sprocket 88.,

As seen in Fig. 9, the end walls of rolls II and i2 may both be notched as shown at 83' and w to receive the transverse portions of the gripping mechanism, namely the crossbar 52' and the shaft 53'. 7

Of course, the notches 85 would likewise be provided as explained in connection with Fig. 1.

around the blanket roll and away therefrom for stripping the sheet from the blanket roll and delivering it at the desired point of delivery.

2. An offset printing press including a blanket roll, a platen above the blanket roll, and registration and delivery means including gripping means, means causing the gripping means to approach the roll, close upon the leading end of a sheet to be printed, assume a fixed position with respect to the roll and rotate about half a revolution with the roll, pass away from the roll generally toward the direction from which it approached the roll, and open to release the sheet The anvil 9| has been illustrated as one flange of the angular crossbar 52', this flange being slotted at 92 to receive the stop fingers ll". It should be observed that the size of the notches 83' and 84' and the slot 92 are such that there is no contact between the portions of the gripping mechanism carried by the chain and any other rotating mechanism except the sprocket wheels carrying the chains. This permits the press to be quite quiet in operation.

Except for the difi'erences mentioned and apparent from the drawings, the construction and operation of the form of the invention shown in Figs. 8 and 9 may be the same as that of the form shown in Figs. 1 to 7.

From the foregoing it is seen that a press is provided having in conjunction therewith a chain delivery which is in its simplest possible form in that it comprises a single loop and extends around the shaft of one of the printing rolls so that a minimum of shafts and working parts may be used. Furthermore, the chain delivery drops the sheet p'rinted-side-up so that the condition of the printing may be observed. In addition, the sheets are discharged at a position underneath the feeding conveyor table so that the overall length of the entire machine may be a minimum. In spite of this simplicity there is no interference with the accurate registration of the sheet since registration means may be pro-' vided in the same manner as if the chain delivery were not provided or extended around a different shaft than either of those on which the printing rolls are mounted. Furthermore, ac-

cording to one fonn of the invention additional simplification is possible by omitting the gripping fingers from the printing roll and letting the gripping fingers of the chain delivery perform their function, accurate registration-being -obtained nevertheless by virtue of the mounting of the stop fingers on the printing roll and designing the machine so that the gripping fingers are used only during the time that they are stationary with respect to the roll, irrespective of ata point remote from the roll; means for feeding a sheet into the gripping means, and registration stop means which, as the gripping means ,closes on the sheet, is associated with the gripping sheet to be printed, assumea fixed position with whether or not they may be in exactly the same a position with respect to the roll the next time they are used for registration.

I claim:

1. An offset printing press including a blanket at that time and for closing at least part of them while the sheet is pressed against the stop means to hold the sheet in registration, at least part of the grippers being carried by endless means respect to the roll, pass away from the roll, and open to release the sheet at a point remote from the roll;-means for feeding a sheetinto the grip ping means, and registration stop means which,

as the gripping means closes on the sheet, is associated with the gripping means and is in an exactly predetermined position circumferentially with respect to the roll, to registerthe sheet with the roll.

4. An offset printing press including a blanket roll, a platen above the blanket roll, and registration and delivery means including chains each forming a simple closed loop extending around the axis of the blanket roll and off to one side thereof, gripping means carried by, the chains, approaching the blanket roll and opened to receive a sheet at the upper side of the blanket roll, closed upon the sheet, and opened to release the sheet after passing around the blanket roll and carrying the sheet away therefrom, and registration stop means associated with the grip ping means at the time that the sheet is fed thereto, the stop means being accurately positioned with respect to the blanket roll.

5. A printing press including two printing members, one of which is a roll coacting with the other to form a bite, registration stop means carried by one of the printing members, means for feeding a sheet toward the bite and against the stop means, grippers carried by the member which carries the stop means, means for opening the grippers to receive the sheet, closing them to hold the sheet in registration for the printing thereof, and subsequently opening them to release the sheet, a second set of grippers carried by endless means extending around the axis of the roll, and moved by the endless means through the bite approximately in alignment with the first grippers and away from the roll, and means for opening the second grippers as them open until the sheet has been seized by the bite, thereafter closing the second grippers to engage the sheet and carry it away from the roll after the first grippers have opened, and for opening the second grippers to release the sheet at the desired delivery point.

6. A printing press including two printing membe s, one of which is a roll coacting with the other to form a bite, registration stop means carried by one of the printing members, means for feeding a sheet toward the bite and against the stop means, grippers carried by endless means extending around the axis of the roll, and moved by the endless means through the bite and away from the roll, and means for opening the grippers as the sheet is fed against the stop means, closing the grippers to engage the sheet while the sheet is pressed against the stop means by the feeding means, held in registration for printing, and carried away from the roll, and for opening the grippers to release the sheet at the desired delivery point.

7. A printing press including two printing members, one of which is a roll coacting with the other to form a bite, registration stop means and grippers carried by the roll, means for feeding a sheet toward the bite and against the stop means, means for opening the grippers to receive the sheet, closing them to hold the sheet in registration for the printing thereof, and subsequently opening them to release the sheet, a second set of grippers carried by endless means extending around the axis of the roll, and moved bythe endless means through the bite approximately in alignment with the first grippers, and away from the roll, and means for opening the second grippers a the sheet is fed against the stop means, holding them open until the sheet has been seized by the bite, thereafter closing the second grippers to engage the sheet and carry it away from the roll after the first grippers have opened, and for opening the second grippers to release the sheet at the desired delivery point.

8. A printing press including a rotating unit, a first set of grippers carried by the rotating unit, a second set of grippers carried by endless means extending around the rotating unit and away therefrom, the two sets of grippers being in alignment with one another for a substantial part of the revolution of the rotating unit, means for opening the second grippers to receive a sheet which during a part of the period of alignment is gripped by the first grippers, and means for closing the second grippers on the sheet and opening the first grippers during the remainder of the period of alignment to pass the sheet to the control of the second grippers whereby the sheet will be drawn away from the rotating unit by the second grippers.

9. The combination of a printing press including a printing roll, chains extending partly around the axis of the printing roll, rotating with the printing roll and extending away therefrom, gripping means carried by the chains and at times rigidly disposed with respect to the printing roll, means for feeding a sheet to the gripping means, and in predetermined registration with the printing roll, means for opening the gripping means to receive a sheet as it is fed to the gripping means and for closing the gripping means after the sheet is fed thereto, and while the gripping means is held rigidly disposed with respect to the printing roll and means for again opening the gripping means after the gripping means has carried the sheet away from the printing roll to release the sheet at the desired delivery point.

10. A printing press including two printing members, one of which is a roll coacting with the other to form a bite, registration stop means located in the same circumferential position with respect to the roll for successive sheets being printed and rotating with the roll during at least a part of the feeding and printing operation, means for feeding a sheet toward the bite and against the stop means. flippers carried by end-- less means extending around the axis of the roll, and moved by the endless means through the bite and away from the roll, and means for opening the grippers as the sheet is fed against the stop means, closing the grippers to engage the sheet while the sheet is pressed against the stop means by the feeding means, held in registration for printing, and carried away from the roll, and for opening the grippers to release the sheet at the desired delivery point.

11. A printing press including two printing members, one of which is a roll coacting with the other to form a bite, gripp rs carried by endless means around the roll, through the bite and away from the'roll, registration stop means rigidly located circumferentially of the roll with respect to the grippers and in alignment with the grippers at the time that the sheet is fed thereto. means for feeding a sheet toward the bite and into the grippers, and means for opening the grippers as the sheet is fed thereto, closing the grippers to engage the sheet while the sheet is pressed against the stop means by the feeding means, held in registration for printing, and carried away from the roll, and for opening the grippers to release the sheet at the desired delivery point.

12. A printing press including two printing members, one of which is a roll coacting with the other to form a bite, grippers carried by endless means around the roll, through the bite and away from the roll, registration stop means rigidly located circumferentially of the roll with respect to the grippers and in alignment with the grippers at the time that the sheet is fed thereto, means for feeding a sheet toward the bite and into the grippers, and means for opening the grippers as the sheet is fed thereto, closing the grippers to engage the sheet while the sheet is pressed against the stop means by the feeding means, held in registration for printing, and carried away from the rolLand for opening the grippers to release the sheet at the desired delivery point, said roll being free of sheet-gripping means other than the grippers carried by the endless means.

13. An offset printing press including a blanket roll, a platen above the blanket roll, registration stop means carried by the blanket roll, feeding means adapted to feed sheets against the stop means, grippers associated with the blanket roll at least at the time a sheet is fed to the stop means, and means for holding said grippers open at that time and for closing at least part of them while the sheet is pressed against the stop means to hold the sheet in registration, the grippers being carried by endless means around the blanket roll and away therefrom for stripping the sheet from the blanket roll and delivering it at the desired point of delivery; said blanket roll being free of sheet-gripping means other than the grippers carried by the endless means.

14. The combination of a printing press including a printing roll, chains extending partly around the axis 01. the printing roll, rotating with the printing roll and extending away therefrom, gripping means carried by the chains and at times rigidly disposed with respect to the printing roll, means for feeding a sheet to the gripping means, and in predetermined registration with the printing roll. means; for opening the gripping means to receive a sheet as it is fed to the gripping means and for closing the gripping means alter the sheet is fed thereto and while the gripping means is held rigidly disposed with respect to the printing roll. and means for again opening the gripping means atter the gripping means has carried the sheet away from the printing roll to release the sheet at the desired delivery point, said chains being endless and carrying said gripping means around a loop to turn the sheet over between the printing oi the sheet and the release of the sheet whereby the printed face of the sheet is visible when delivered.

15. The combination or a printing press including a printing roll, chain extending partly around the axis of the printing roll, rotating with the printing roll and extending away thereirom, gripping means carried by the chains and at times rigidly disposed with respect to the printing roll, means for feeding a sheet to the gripping means, and in predetermined registration with the printing roll, means for opening the gripping means to receive a sheet as it is fed to the gripping means and for closing the gripping means after the sheet is fed thereto and'while the gripping means is held rigidly disposed with respect to the printing roll, and means for again opening the gripping means after the gripping means has carried the sheet away from the printing roll to release the sheet at the desired delivery point, said feeding and registering means including stop means positioned unitormly with respect to the printing roll each time the gripping means receives a sheet for cooperating with the'gripping means and accurately registering a sheet with respect to the printing mil.

16. A printing press including two printing members, one 01' which is a roll coacting with the other to form a bite, a set of grippers carried by endless means around the roll, through the bite and away from the roll, registration stop means having the same position circumferentially or the roll for successive sheets ted thereto and, at the time each sheet is fed thereto, being rigidly located circnmi'erentially of the roll with respect tothe grippers and in alignment with the grippers, means for feeding a sheet toward the bite into the grippers and against the stop means, and means for opening the grippers as the sheet is fed thereto, closing the grippers to engage the sheet while the sheet is pressed against the stop means by the feeding means, held in registration for printing, and carried away from the roll, and for opening the grippers to release the sheet at the desired delivery P int.

WILLIAM WARD DAVIDSON. 

